Preparation

Sift first 3 ingredients into bowl. Mix in yogurt and 1/4 cup goat cheese. Knead on floured surface until smooth and elastic, about 10 minutes. Form into ball. Return to bowl; cover with plastic. Let rest 2 hours (dough will not rise).

Melt butter in large skillet over medium heat. Add onions; sauté until deep golden, about 25 minutes. Season with salt and pepper. Cool. Set aside. Turn dough out onto floured surface. Divide into 4 pieces. Form each into ball. Roll out each to 8-inch round.

Brush heavy medium skillet with olive oil; heat over medium-high heat. Add 1 dough round and cook until brown spots appear all over bottom, about 5 minutes. Turn bread over and cook until brown spots appear all over second side and bread is cooked through, about 5 minutes. Transfer to large baking sheet. Repeat with remaining dough rounds. (Can be made 2 hours ahead. Cover onions and bread separately; let stand at room temperature. Rewarm bread uncovered in 350¡F oven about 5 minutes.)